Shock-absorbing attachment for crutches



June 3, 1930. M. H. SULLIVAN 5 SHOCK-ABSORBING ATTACHMENTFOR CRUTCHES Fil ed Oct. 13, 1928 MZZAYZZZZZZQIZ m L Patented June 3, 1930 MICHAEL H. SULLIVAN, OF WILKES-BARREL PENNSYLVANIA SHClCK -ABSORBING ATTACHMENT FOR CRUTCI-IES Application filed. October 13, 1928. Serial No. 312,343.

require the use of special fastening means for holding the partsproperly assembled.

A further object is to provide an attachment having interfitting parts which, when assembled, are held against displacement relative to each other.

I/Vith the foregoing and other objects in View which will appear as the description proceeds the invention resides in the combination and arrangement of parts and in the details of construction hereinafter described and claimed it being understood that changes in the precise embodiment'of the invention herein disclosed may be made within the scope of what is claimed without departing from the spirit of the invention.

In the accompanying drawings the preferred form of the invention has been shown.

In said drawings,

Figure 1 is a side elevation of a crutch having the present improvements combined therewith.

Figure 2 is an enlarged section on line 2-2, Figure 1.

Figure 3 is a section on line 3 -3, Figure 2.

Figure 4 is a section on line 4-4, Figure 2.

Referring to the figures by characters of reference 1 designates the shank of the crutch provided with an annular groove 2 and with a radially disposed bore 3 between the end ofthe shank and the groove 2. The foot 4 of the crutch is in the form of a cylindrical member having a tip 5 at its lower end while a radial bore 6 is extended thereinto near its upper-end. A coiled spring 7 is interposed between the shank 1 and the foot 4 and is provided, at one end, with an angular arm 8 which extends within a longitudinal groove 9 in the periphery of the shank 1 and thence within the radial bore 3. This is clearly shown by dotted lines in Figure 2 andin section in Figure 3. The other end of the spring has an angular arm 10 arranged within a short longitudinal groove 11 in the periphery is fitted'around shank 1 and has an annular depression 13' seated in the groove 2. This sleeve houses the spring 7 and serves to hold the angular arm 8 within the groove 9 so that the end portion cannot be withdrawn from the bore 3.

The sleeve 12 also surrounds the upper end portion of the foot 4 and serves to hold the arm 10 in the groove 11 and bore 6. Foot 4, however, can reciprocate in the sleeve and when the crutch is subjected to downward pressure it can shift downwardly relative to the foot, thereb placing the spring 7 under compression. gbviously this spring will thus constitute a shock absorber.

Importance is attached to the fact that the sleeve 12 not only serves to house the spring 7 and to guide the foot 4 but also acts as a means for holding the ends of the spring in engagement with the shank 1 and the foot 4. No special fastening means are required for this purpose. Therefore the structure is very cheap to manufacture and can be assembled readily. Furthermore there are no parts to get out of order.

What is claimed is:

The combination with a crutch shank having aradial recess and a longitudinal groove, of a foot having a longitudinal groove and a radial recess, a coiled springinterposed between the shank and foot having end portions seated snugly'in the respective grooves and recesses, and a sleeve crimped upon the shank and housing the spring and a portion of the foot to hold the ends of the springs in the grooves and recesses, said foot being slidable.

In testimony that I claim the foregoing as my own,I have. hereto affixed my signature.

MICHAEL H; SULLIVAN.

of the foot 4 and having its terminal extend- 7 ing into the radial bore 6. A guide sleeve 12 

